def test_process_frequencies():
"""The right nodes are in the list."""
expected = {l: i for i, l in enumerate(("a", "b", "c", "d", "e"), start=1)}
stream = "".join(itertools.starmap(operator.mul, expected.items()))
freqs = set(process_frequencies(stream))
assert freqs == {CharNode(l, f) for l, f in expected.items()}
def test_stream_counter_data(data_file):
"""The function that processes the frequencies correctly."""
freq_processed = process_frequencies(data_file)
mapped_result = {node.value: node.freq for node in freq_processed}
expected = Counter(data_file)
assert mapped_result == expected
def test_preffix_free(data_file):
"""The internal table generates new variable-length prefix-free code."""
freqs = process_frequencies(data_file)
t = create_tree_code(freqs)
table = parse_tree_code(t)
codes = deque(table.values())
for code_to_check in codes:
prefix = {c for c in codes if c.startswith(code_to_check)}
assert prefix == {code_to_check}
def test_process_empty_frequencies():
"""For '' -> []."""
assert process_frequencies("") == []
def test_frequencies_add_up(data_file):
frequencies = process_frequencies(data_file)
checksum = sum(c.freq for c in frequencies)
expected = sum(Counter(data_file).values())
assert checksum == expected